#!/usr/bin/env python
# -*- coding: utf-8 -*-

from urllib import urlretrieve

def firstNonBlank(lines):
    for eachLine in lines:
        if not eachLine.strip():
            continue
    else:
        return eachLine

def firstLast(webpage):
    f = open(webpage)
    lines = f.readlines()
    f.close()
    print firstNonBlank(lines)
    lines.reverse()
    print firstNonBlank(lines)

def download(url='http://www.hao123.com', process=firstLast):
    try:
        retval = urlretrieve(url)[0]
    except IOError:
        retval = None
    if retval: # do some processing
        process(retval)

if __name__ == '__main__':
    download('http://cn.bing.com')